URL shortening services are popularly used on Twitter, Facebook, IM's, etc. As history has proved, putting your URL's in the hands of a public URL shortening service could annihilate your linking history.
Shortcut allows you to host your own service. Plus, it just looks sweeter when it's your own domain! Shortcut allows you to create shortened URL's, similar to the services offered by sites like tinyurl.com and bit.ly, anywhere in your CP with the Shortcut accessory. You can also automate shortcut URL's for your entries with the Shortcut fieldtype, that works with both the CP Publish page and SafeCracker. Shortcut will automatically generate shortened URL's and save them to the Shortcut field upon submitting and editing your channel entries. Set it up once and forget about it! You can also create custom keys in the event you want to have more readable URL's. And lastly, Shortcut offers simple tracking for each click on a shortcut URL.
The following two URL's are examples of a random shortened URL and a custom shortened URL that should take you back here:
NOTE: Documentation for Shortcut 1.x can be found here.